PRESSURE CONTROL DEVICE FOR A TYRE INFLATING SYSTEM WITH A ROTARY FEEDTHROUGH, AND TYRE PRESSURE CHANGING METHOD

A pressure control device for a vehicle tire inflating system is configured to receive compressed air via a ventilating inlet, activate at least one seal for sealing an air chamber between a stator and a rotor of a rotary feedthrough via a seal actuating outlet, and ventilate a tire at a ventilating outlet pressure via a ventilating outlet and the feedthrough. A control valve is pneumatically controllable by a control pressure, the ventilating outlet being ventilated at the outlet pressure by the control valve only when the control pressure is at least a defined minimum pressure. In response to pressure build-up at the ventilating inlet at least to the minimum pressure, the control pressure and the seal actuating pressure are built up for ventilating, but build-up of the control pressure is delayed with respect to the seal actuating pressure. Activation of a seal prior to ventilation of the ventilating outlet is possible without additional actuating channels.